I did, in the end, get down to it and do some real work (actually, I had already done some when I posted my first message, just not very much).

Cocoa development really is fascinating; it’s so different from the mess we developers have to put up with on other systems… not only have we got the UN*X APIs underneath, but we’ve got a really neat object system and a decent framework designed by someone that actually knows about OOD. And to think it was all around in the 1980’s!